This almost exactly describes 2 of my most recent exes when they were with me. Good luck and I hope you get it sorted out. It can be very confusing to be a man in an intimate relationship with a woman who only identifies as “lesbian”, likewise I’m sure it can be equally confusing for someone who identifies as such and yet feels they are developing feelings for a man. You will figure it out, all the best.
Dump him and date a woman, see if that suits you better :)